BRAIDING MACHINE 



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menstruum sufficiently cheap in France, on account of the low duty upon alcohol, or of 

 naphtha. There are medicated bougies, the composition of which belongs to Surgical 

 Pharmacy, The manufacture of these instruments of various kinds forms a separate 

 and no inconsiderable branch of industry at Paris. Very superior bougies are now 

 made by the surgical-instrument makers, and by the workers in caoutchouc, in this 

 country. 



BOULDER. CXiAV. The fine laminated clays of the Pleistocene epoch, which 

 immediately overlie the true Boulder clay of geologists so called from the boulders 

 and pebbles interspersed through their mass. 



BOUXiDERXNG STONE. A name given by the Sheffield cutlers to the smooth 

 flint pebbles with which they smooth down the faces of buff and wooden wheels. 



BOURIJONITE. A sulphide of antimony, lead, and copper. According to 

 Eammelsberg, sulphur 19'77. antimony 24'34, lead 42'88, copper 13'06. It is found 

 in several parts of Cornwall and Devonshire, and in many of the mining districts of 

 Europe. 



BOVEY COAIi. A lignite found in large deposits at Bovoy-Tracey, in Devon- 

 shire, whence its name. See LIGNITE. 



BOW PENT. A drawing pen. The parts which hold the ink is formed of two 

 pieces, which are bowed out and adjustable by a screw. 



BOWSTRING HEMP. A fibre prepared from the Sanscviera Zeylanica. See 

 HEMP. 



BOX WOOD. (Buis, Fr. ; Buchsbaum, Ger.) Buxus sempervirens. Two 

 varieties of box wood are imported into this country. The European is brought from 

 Leghorn, Portugal, &c., and the Turkey box wood from Constantinople, Smyrna, 

 and the Black Sea. English box wood grows plentifully at Box Hill, in Surrey, and 

 in Gloucestershire. The English box wood is used for common turnery, and is 

 preferred by brass finishers for their lathe-chucks, as it is tougher than the foreign 

 box, and bears rougher usage. It is of very slow growth, as in the space of 25 years it 

 will only attain a diameter of li to 2 inches. Boxwood is used for making clarionets 

 and flutes, carpenters' rules, and drawing scales, and is exclusively employed by the 

 wood engraver. Its sawdust is used for cleaning jewellery. See ENGRAVING ON 

 WOOD. 



BRACES. (Bretellcs, Fr. ; Hosentrdger, Ger.) Narrow fillets or bands of leather 

 or textile fabrics, which pass over the shoulders, and are attached behind and before 

 to the waistbands of trousers, for supporting their weight. Braces are now made of 

 an elastic material, into the structure of which Indian-rubber fibre enters. 



BRAHMIN'S BEADS. The seeds of a species of Elaiocarpus, which are capped 

 with silver and made into necklaces and bracelets. 



BRAID. A plaited, twisted or woven trimming. 



BRAIDING MACHINE. (Machine it lacets, Fr. ; Bortenwerlcerstuhl, Ger.) 

 This being employed, not only to manufacture stay-laces, braid, and upholsterers' cord, 

 but to cover the threads of caoutchouc for weaving brace-bands, deserves a description 

 in this work. Three threads at least are required to make such a knitted lace, but 11, 

 13, or 17, and even 29 threads are often employed, the first three numbers being 



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205 



preferred. They are made by means of a frame of a very ingenious construction, 

 which moves by a continuous rotation. Wo shall describe a frame with 13 threads, 

 from which the structure of the others may be readily conceived. The basis, of tho 



